www.ourcoolhouse.com Our Cool House is a Web site created by a man and his wife to document construction of their earth-sheltered home in Deep Creek Lake, Md. Very detailed drawings and information, links, photos.

So when he built a house on the half-acre lot he'd bought in Collier in the early '80s, he opted for a design that was unusual for this area, an earth-sheltered home.

"It seemed like a sensible thing to do to save energy," he says.

One of the most technologically advanced houses in the neighborhood when it was built (not to mention the most curious-looking), the 17-year-old, single-level contemporary has recently come on the market. It has been priced by Coldwell Banker's Mt. Lebanon office at $164,900.

Granted, this eco-friendly house takes some getting used to. From the top of the paved driveway on Sixth Street, it looks like nothing more than a large, grassy mound. It's only when you get about halfway down the hill that you catch a glimpse of the concrete and cedar front entrance cut into the hillside. Then, if you wander into the back yard and see the full length of the windowed facade, you realize that this is a house, albeit an unconventional one.

Designed by Bob Kobet, a nationally known Pittsburgh architect who specializes in energy-efficient and environmentally sound building design, the 1,700-square-foot house is one of just a handful of earth-sheltered residences in Allegheny County. Still, it should appeal to anyone who's looking for a ranch-style home with superior construction or perhaps something that's "just a little bit different," says Realtor Mary Ann Wellener.

Bilbo Baggins and his fellow Hobbits aside, earth-sheltered housing isn't as unusual as you might think. In Northern China, more than 10 million people live below ground. In the United States, where the modern revival of earth-sheltered dwelling began in the early '70s, an estimated 100,000 homeowners have gone subterranean.

The entrance and driveway to the home. (Bill Wade, Post-Gazette)

You might expect a house built beneath 2 feet of earth to be cavelike and perhaps even damp. But this south-facing house is anything but a dreary hole in the ground. All of the living areas feature large box bay windows that flood the interior with natural light. The 23- by-13-foot living room, which opens onto the level back yard through French doors, is especially bright.

Like many earth houses, the home is made of poured concrete and features a grass-covered soil roof. It's extremely energy-efficient because so much of it is underground, where the temperature remains between 50 and 60 degrees year-round. In winter, there is no wind-chill to worry about and in summer, residents don't have to worry about the baking sun. Brown estimates he saves at least 50 percent on heating and cooling costs compared with a conventional home of this size.

There are other benefits as well. The house is completely fire-resistant and extremely peaceful and quiet. It is also storm-proof. So much so that sometimes Brown and his wife aren't even aware it's raining.

"Nothing moves, nothing rattles," he says.

Long and narrow, the house is divided by the living room/dining area into two separate wings, all painted in a neutral color scheme with oak trim. The western half holds the carpeted master bedroom, which measures 15 by 13 feet and contains deep, walk-in closets and a full bath with both tub and shower. The adjoining 11- by 10-foot bedroom is currently used as a home office.

The other wing has two more bedrooms and another full bath, as well as a 16- by 10-foot family/game room with easy-to-clean vinyl flooring. The integrated utility area, hidden behind several sets of bi-fold doors, could just as easily hold an entertainment unit.

The open living room and dining areas of the home lead into the kitchen, seen in the background. (Bill Wade, Post-Gazette)

The U-shaped kitchen has oak-grain laminate cabinetry, a double sink and cream-colored counter tops and opens onto the 11- by 9-foot dining area.

Outfitted with a heat pump and radiant heat panels in the ceiling as well as central air, the house is zoned so homeowners are able to heat or cool only certain rooms.

The only external maintenance -- other than a weekly mowing of the roof during the warmer months -- is a coat of stain on the cedar siding every four or five years.

The backyard is landscaped with flowering plants and ornamental grasses including rose of Sharon, yucca, mountain laurel, rhododendron and pampas grass, which grows to more than 5 feet high. There is also a small campfire area nestled into a corner of the wooded hillside and a basketball hoop on the driveway.

The additional green space provided by the earthen roof not only makes the lot seem larger but serves as a garden (one patch is planted with asparagus.) It also provides more room for family activities. Kids can actually sled-ride off the roof when it snows and in summer, it's the perfect spot to watch fireworks, Brown says.

Less than a mile from Interstate 79, the house is a 10-minute commute to Downtown and a 15-minute drive to Pittsburgh International Airport and the shops and restaurants at Robinson Town Centre.

"It's close to everything yet still feels almost rural because it's so private," says Wellener.